Documentation - FAQs

Below are frequently asked questions.

General Info

  1. How do I get help?
  2. How do I get an Account? For a visitor?
  3. How do I login? What are my options?
  4. How do I logout? How often should I logout?
  5. What can I do about SPAM and how can I protect myself from suspicious/malevolent emails?
  6. How do I reboot? Should I reboot?
  7. What is backed up and how often? How do I restore a file?
  8. How much disk space can I use?
  9. How do I print from Linux?
  10. How I setup a personal/class webpage?

Hardware Resources

  1. Where are the public printers?
  2. What classrooms have computers and how do I use them?
  3. Do we have a scanner and how do I use it?
  4. How do I scan a document into my account?
  5. Where should I run large computational jobs? Do we have a cluster?

Basic Applications

  1. What is a command prompt? How do I get one?
  2. How do I read my e-mail?
  3. How do I change my password?
  4. How do I set my default printer?
  5. What program do I use to do ... ?
  6. How do I burn a CD-ROM?

Advanced Software Questions

  1. Where can I find documentation on Latex (TeTeX)?
  2. How do I create a PDF file from a Postscript or DVI file?
  3. How can I use graphics with pdflatex?
  4. How do I Move, Copy, or Delete a File from the Command Line?
  5. How can I post password protected web pages and files?
  6. How do I allow certain users access to my files? What are ACLs?
  7. How can I use PGP with Pine?

Home Computers and Laptops

  1. How do I access my account remotely?
  2. How can I use VNC for remote sessions?
  3. Can you install linux on my home computer/laptop? Can you fix my home computer/laptop?
  4. Can I print from my laptop via the wireless network?
  5. How can I mount my home directory from my home Linux machine?
  6. How can I mount my home directory from my home Windows or MacOSX machine?

How do I get Help? Who do I call?

The best, fastest, and most efficient way to get help is to mail req@math.duke.edu with a description of your problem. This will send your message to all our systems administrators and allow them to respond from where ever they may be at the time. Email is by far the best way to reach us. You should receive an automated confirmation message letting you know the email was received by the system.

Calling your Systems Administrator should be reserved for emergency situations. An Emergency is defined as when you are unable to Email.

We ask that you do this for a couple of reasons. First is that we are frequently juggling several tasks and a phone call essentially disrupts this process and forces us to address your questions immediately without time to think about it. You will get better, more complete, and more polite answers we are not interrupted regularly. If a more involved discussion is required, we can make an appointment and meet with you or arrange a call to work on the problem. The second reason is that it establishes a record of problems that we have worked on and solutions we have devised. There is nothing more frustrating than to have a user call with an unusual problem, which we work on solving and answering after recommending they use email, only to have another user encounter a similar problem months later and we can't remember how we solved it the first time. Email creates a nice paper trail, especially for the administrator that didn't work on the problem the first time.

Finally, we are often not at our desks, but can get to email virtually anywhere. When possible, we answer your email as soon as we get it. We try to stay on top of problems and solve them as priority will dictate.

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How do I get an Account? For a visitor?

Account applications are made online at https://services.math.duke.edu/cgi-bin/account. All regular members of the Mathematics Department (undergraduate major, graduate student, postdoc, faculty, or staff) are eligible. If an account is required for a visitor or someone who is not a regular member of the Mathematics Department, either apply online or have them apply online and be sure to include the name of a faculty sponsor and/or the number of a Mathematics Class for verification. We reserve the right to refuse any application.

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How do I login? What are my options?

Logins are done through a graphical screen with fields for Username and Password. If the computer is at a text screen with a Login:prompt, then it is not ready for use. Try pressing ALT-F1 to see if the usual graphical screen comes up. If not, try another computer and email req@math.duke.edu so we can fix the problem.

To login, enter your username, press Tab to switch to the password field, then enter your password. Asterisks (*) will appear as you type your password so that others cannot read it. To login with the default environment, press Enter after entering your password. You can select the environment to login with by choosing from the Menu:button and then from the Session Type menu. The most common selections are GNOME and KDE although there are several other, less functional but also faster, desktop environments available.

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How do I logout? How often should I logout?

Logging out is dependent upon the desktop environment you are currently using. If you are using the default MATE environment, click on the Main Menu icon on the taskbar (usually on the left side) and select Log out... You will be asked to confirm your decision. If you are using Gnome, click on your name on the top bar and then choose Log out.

In a pinch, if applications have locked up or the logout process is having problems, press the keys Control-Alt-Backspace at the same time. This will do a forceful logout.

WARNING: Data from applications that are open will not be saved and no confirmation will be given. Use carefully.

How often should you logout? Logging out frees memory from applications and generally cleans out things. If things seem to be running slower than usual, logging out and back in might be the easiest way to return to normal. As a general rule of thumb, if you have a computer for personal use on your desk and you are going to be away for more than one day, it would be good to logout (such as a weekend). If you are using a public computer, such as one in the labs or a common computer in a graduate office, and are going to be away for more than one hour, you should logout to allow others to use the computer while you are gone. Another reason to logout is that we are constantly performing updates on systems in the department. On rare occasions, a reboot is required. Fortunately these are much rarer than on Windows. We try to arrange reboots around times when people are not logged in, but there are always a few users who do not logout for months and special attention is required to arrange a time to reboot their machine. Logging out when you are out of the office for a couple of days gives us the chance to reboot with disrupting your schedule or our schedule.

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What is a command prompt and how do I get one?

The command prompt is a text based application that provides direct interaction with the Unix system. It is similar in context to MSDOS or the Command Prompt window you can bring up on Windows systems. A listing of basic commands with documentation is available at http://www.tldp.org/LDP/abs/html/basic.html. In general, most things can be done through the graphical user interface. But sometimes we will ask you, or it may be quicker and easier, to use the command prompt.

In most desktop environments, the command prompt can be found in the Main Menu under System Tools and is called Terminal.  As a shortcut, you can also press ALT-F2 which brings up a Run box. You can enter any command here that you would enter at the command prompt and it will execute directly.

From the command prompt, you can execute almost all programs by just typing the program name, sometimes with an argument such as a file to edit or display. For example, you can run the following programs by typing their command names:

  • mathematica
  • xmaple
  • matlab
  • firefox
  • thunderbird
  • google-chrome

There are many more programs available than are possible to list. If you are looking for something specific, email req@math.duke.edu and ask, we'll be glad to help.

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How do I read my e-mail?

There are many applications available for reading email and fortunately, most are compatible with each other and can be used interchangably. The recommended mail client is Thunderbird in the Main Menu under Internet (or from the command line, thunderbird).   

From the command line, we recommend pine, but mutt and the original mail are still available if needed.

Finally, from the Web you can access your email securely via the GDE or Roundcube Mail.

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What can I do about SPAM and how can I protect myself from suspicious/malevolent emails?

Here are a few tips to help you avoid spam and phishing schemes. First you can read more about SPAM and Phishing, two of the most common problems you may encounter when you use E-Mail or surfing the web.

They can come to you as email messages to your mailboxes, web pages you visit or viruses on your computer. About 70% of messages come to our mail server are spam messages nowadays; even though we drop those messages we know for certain are spam, and mark the others as '[SPAM]', there are still some spam messages ending up in your regular mailboxes and some of them look really "real".

We suggest that:

  1. No one (including university administration, OIT, system support staff) at Duke or any reputable company (such as your bank) will ask for any sensitive information such as your SSN, your home address, your login name or your password by email. I'm sure you have received some messages supposedly from OIT or the help desk which ask for your login and password; they are completely fake.
  2. Treat any unsolicited email with suspicion, even those from people you know. For example, we get many messages supposedly coming from members of our department. One good trick is to examine the complete email header (press Control U inside Thunderbird). In particular, look at the lines starting 'Received:' and 'Reply-To:'. If the message was sent or came from a foreign address or an site unrelated to the email, then it is probably fake. If the Reply-To address points to a domain other than the From address, it is probably a phishing attempt. Note that it is ridiculously easy to forge email return addresses and is a very common practice.
  3. Don't click on any suspicious web links in email message if you are not 100% certain. Copy and paste into your browser instead. In addition, hovering over the link will show you the actual address it points to in the status bar on many email applications. If the address shown in the status bar does not match the address shown in the email, do not click on the link.
  4. Don't configure your email reader to download and display images automatically. We recommend displaying all messages in plain text; turn on html/images on per message basis if needed. Most email programs will let you select plain text in the View Menu. Thunderbird by default will not load images unless you click on the "Show Remote Content" or "Load Images" button on each email.
  5. Never send anything sensitive to a web site if you are not sure about its true identity, the connection is not encrypted (not https://) or the URL looks funny. For example, https://www.yourbank.com.sbaco.ie/home.html and https://www.y0urbank.com/home.html are not yourbank. Most importantly, NEVER send passwords via unencrypted email. If you are particularly concerned about a link in a email, don't use the link but go directly to the companies website by manually entering the web address into your browser and login from there.
  6. We recommend (especially for Windows users) using the NoScript and/or Flashblock extensions with your Firefox browser. These extensions do make browsing a bit less convenient, but will certainly help to protect you from certain attacks via web pages. Most of the web phishing schemes depend on javascript to work. It's also a good idea to clear the web browser cache and history after visiting any secure sites (such as your bank).
  7. Don't just surf to sites blindly because you see it in some dubious web sites or blogs. Think before you surf.
  8. Keep your home/laptop Windows system patched and virus scanner up to date.
  9. Check out the following web sites when you have time for some fun reading:
  10. Finally, if something sounds too good to be true, then it probably is. Feel free to check with us if you are unsure.

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How do I change my password?

To change your password, bring up a command prompt console (usually found under the Main Menu icon, then System Tools, then select Terminal) and execute the command passwd. After entering your current password once, you will be prompted for a new password twice, then your password should be changed.

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How do I set my default printer?

You may select one of the public printers or a private printer (with the proper permission) as your default printer. Then any jobs send to a printer without specifying which printer, will go to your default printer. To specify a default printer, you first need to know which shell is your default. Run the command echo $SHELL from a command prompt. It should return one of the following:

  • /bin/bash (Bourne Shell)
  • /bin/csh (C Shell)
  • /bin/tcsh (Enhanced C Shell)

You then need to add a line to a file in your home directory that the shell uses when you login.

For the C Shells/bin/csh and /bin/tcsh you edit the file called .cshrc in your home directory. (If you are unsure how to do so, try the command pluma ~/.cshrc from the command line). Add the following line to the end of the file:

setenv PRINTER lw0

where lw0 is an example of one of the public printers. For the Bash Shell/bin/bash you edit a file called .bashrc in your home directory. Again, you can use pluma ~/.bashrc to edit this file from the command line. In this file you add the following line at the end:

export PRINTER=lw0

where lw0 is an example of one of the public printers.

You will need to logout and login again for this change to take effect.

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How much disk space can I use?

Short Answer: New users have a home directory quota of 30GB. There is no quota for local disk space in /xtmp or /ytmp.

Long Answer: In the last couple of years, the amount of disk space required has doubled about once a year. While disk space is relatively cheap, backup space (which is an absolute necessity) is not.

Thus our first step in this process is to try to eliminate from our backups all files that really should not be backed up to offline storage. This includes all personal MOVIES, MUSIC, PICTURES (those not intended for web distribution on your personal page), and other such files.

We have three categories of disk space available to you (listed in order of cost of resources, highest first) :

A) Home Directory Space (~username)

  • Backed up nightly
  • Available simultaneously from all machines
  • Not as fast

B) Workstation Local Disk (/xtmp)

  • Backed up nightly
  • Fast
  • Available only from local machine (or via ssh connection)

C) Workstation Local Disk (/ytmp) :

  • NOT Backed up
  • Fast
  • Available only from local machine (or via ssh connection)

The /ytmp directory was created to accommodate the large amount of personal files that are being created on our systems that have no business being backed
up nightly (or at all for that matter). If you need to have games, MP3 music, AVI, MPG, MP4, or any other personal material on your office machine, PLEASE PLEASE PLEASE put these files in /ytmp so that they will not consume public disk space or backup resources.

A general rule of thumb is that email, papers you are working on, and code you are writing that needs to run on several computers should be placed in your home directory. Large files, data sets from code runs, archived documents, and anything else that needs to be backed up should go to /xtmp. All other files should be placed on /ytmp.

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What is backed up and how often? How do I restore a file?

For a summary of what is backed up, refer to the FAQ on Disk Usage. Backups are done nightly at 1:30am, although due to the volume of data backed up may not complete until after 3:00am or later. We archive monthly backups for up to 1 year and yearly backups perpetually.

If you delete a file, or worse, many files, email req@math.duke.edu with a listing of what you need recovered and the approximate date of when you want the data recovered from. We will restore the files, possibly in a separate directory, and notify you when the data is available.

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What program do I use to do ... ?

Linux is a very capable operating system that has many applications, several of which perform similar functions but have a wide range of different/missing/extra features. Here are a few applications that are use for common tasks with their names for use from the command line. Most of the programs are also found in the KDE and Gnome menus under the appropriate headings.

  • Microsoft Office Files (.doc, .xls, .ppt): These files can be edited and created most easily with LibreOffice, run soffice from the command prompt. Alternatively, the programs abiword and gnumeric can handle Word and Excel files respectively, and may be faster than OpenOffice, but may be more or less compatible depending on the features of the files.
  • LaTeX, TeX (.tex, .dvi): For editing TeX files, try kile or kwrite. They have context sensitive highlighting and other features to make editing TeX files much easier. Viewing .dvi files can be done with xdvi or kdvi which both provide methods of zooming and printing.
  • PDF (.pdf): The default application for PDF files is Okular. But two other applications exist which may be used if problems arise with okular. They are evince and ADobe Acroread. Acroread is very old and unmaintained, but there are documents that only be read by it so we include it here.
  • MPEG-3 Audio Files/OGG Audio Files (.mp3, .ogg): Music files can be played from programs such as rhythmbox, gstreamer, and even the command line programs mpg123 and ogg123. Be sure to check your volumes with mixers such as pavucontrol or from the command line, alsamixer.
  • Other Audio/Video Files: For other audio/video files, try playing them in vlc or gmplayer.

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How do I scan a document into my account?

There are two ways available to scan documents into your account. Alternatively, there is a scanner in room 102 that can be used. Instructions for this scanner are available here as well as posted above the computer attached to the scanner.

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How do I burn a CD-ROM?

To burn a CD, first check if your machine has a CD drive capable of writing to discs. Stenciled on the front of the drive door should be a logo proclaiming either Compact Disc or Compact Disc Rewritable. If you have a drive with the latter (Rewritable), then you can burn CDs on this machine. Run the program k3b. It should be self explanatory from the menus and prompts, but in short, you tell it to create a new Data CD, drag the files/directories you want to burn to the bottom area, then hit the "Burn" button after inserting a black CD-R in to the disc drive.

The command line programs mkisofs and cdrecord are also available for advanced users.

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How do I reboot? Should I reboot?

Linux machines rarely need rebooting. Several machines in the department have been up and running, and in use, for over 200 days at a time. Occasionally we will need to reboot the machines to install security updates or to perform hardware upgrades. However, one thing to keep in mind is that you are not necessarily the only user using the machine when you are thinking about rebooting. Even it is your personal office machines, administrative scripts may be upgrading software packages, running scans, or managing maintenance tasks. Thus it is preferable to only reboot when absolutely necessary.

If you machine appears to lock up, the first thing to take note of is whether the mouse cursor can still move. If so, the machine is not totally locked up, only the graphical interface. And it may be waiting on some application that is causing the machine to appear hung. First, give the machine about 1 minute to see if it recovers. Restarting file servers, which happens rarely, but does happen, can cause machines to hang for about a minute while the server reboots. After that minute or so, consider whether you really need to recover control and get back to your programs that are running or if logging out is a sufficient alternative. Pressing CTRL-ALT-BACKSPACE should kill the graphical session, log you out, and allow you to login again. If that fails, you can try contacting us by phone and then hit the reset button to reboot the machine. If you want to try regaining control, you can remotely login to your machine via ssh from another machine, and if you gain access, kill off processes one at a time until you regain control or it becomes clear a logout is the only solution. You can contact us to take a look at a machine remotely to help you kill processes.

If the mouse no longer moves, it is very likely the machine is totally hung. It would be preferable to check CTRL-ALT-BACKSPACE and possibly try logging in remotely via ssh to verify the machine is inaccessible, but after, rebooting is your only option.

IMPORTANT NOTE: If you machine crashes regularly, that is a good indication of either a major hardware problem or a bad software issue and we should attempt to correct it. It is difficult for us to know the difference between a reboot caused by tripping over a power cord and one caused by a machine locking up. So if you are having consistent problems with a machine, let us know so we can take a more detailed look.

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How do I access my account remotely?

There are several ways to access your account remotely. The simplest way is through the command line interface provided via ssh. There are SSH clients available for Mac OSX, Windows, and Linux that will allow you to access a command prompt for almost any machine in the department. From the command prompt, you can run any text-based applications, and with a fast enough connection and a X server capable local machine, even run graphical applications remotely.

The second way is via the web. The suite of programs in the GDE provides you with access to email, files, remote desktop, mail forwarding, vacation message management, a web proxy, and SSH access.

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How can I use VNC for remote sessions?

Why VNC?

VNC is a remote display protocol that works well over slower connections. It will let you run graphical programs such as Matlab and Maple remotely in a virtual session. In addition, this session will continue to run until explicitly terminated. You use a VNC viewer to connect to the session and control it but you can disconnect at
any time and return later.

Initial Setup

First, connect via SSH to the machine you want to run your VNC session on, cauchy.math.duke.edu would work or you can use the machine in your office if you have one.

Once logged in, run:

vncserver -geometry XxY

where XxY is the resolution of the virtual screen you want to create, 800x600 or 1024x768 are good choices. The larger it is, the slower, but over Duke LAN connections, it doesn't make too much difference.

When you run this command, it will return the screen ID to you, something like cauchy:5. Remember this. This screen (cauchy:5) will continue running until you expicitly kill it or the machine reboots so you can keep connecting and using it. Just closing the VNC viewing window will not kill the session.

Now set your VNC password by typing:

vncpasswd

and entering a password twice. You only need to do this once, after that, the vnc password will be set for all future sessions.

Connecting from Linux

That's the setup part, now to connect to your screen whenever you want to do some work, you need a VNC viewer with SSH capability.

If you are running linux on your machine, you can try connecting with the command:

vncviewer -via username@remotehost remotehost:display

which following our example above would be something like (replacing joe_user with your username):

vncviewer -via joe_user@cauchy.math.duke.edu cauchy:5

This will ask for your SSH password first, then your VNC password.

Connecting from Windows

Install the SSVNC viewer, available here:

SSVNC: SSL/SSH VNC viewer

Tell it to use SSH for the connection, use cauchy.math.duke.edu as the proxy/gateway, and connect to your VNC session you set up in the initial setup, in this example cauchy:5.

Closing the connection

Just close the window when you are done and you can reconnect anytime later and resume your session.

To really kill the VNC session, logout of the Panel and it will close the VNC server.

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Where should I run large computational jobs? Do we have a cluster?

We do have a cluster of machines running Sun's Grid Engine software to manage jobs. The machine grid1.math.duke.edu through grid16.math.duke.edu are available for running long computational jobs, but it is preferable to submit these jobs through the Sun Grid Engine (SGE) interface on grid.math.duke.edu so that resources are utilized with maximum efficiency. Read the documentation for submitting and monitoring jobs.

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Can you install linux on my home computer/laptop? Can you fix my home computer/laptop?

We are available to assist you with your home computers and laptops, however keep in mind that our primary jobs are maintaining the 180 or so computers in the department and supporting the 100 or so regular users so our assistance will be strictly as time permits. Contact us in advance to discuss what needs to be done and to schedule a time when we can work on your machines. We can install linux on your computer with the exact same setup as the ones in the office (with the exception of Matlab for which you will need to purchase a license) and can even install it alongside an existing Windows installation. You will need at least 30GB of free disk space for linux. A typical install will take about 3 hours for a clean install, 5 hours for an installation along side Windows, or about 5 hours for an upgrade (since we have to backup your old data first, then install, then restore your data). As you can see it can be rather time consuming so if you are bringing by your computer, be sure to get it here in the morning (before 10am) if you expect it back by the end of the day.

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How I setup a personal/class webpage?

Creating Personal/Class Webpages

You can set up personal or class webpages inside your home directory within a subdirectory called public_html. All files and directories placed in this subdirectory will, with proper permissions, be accessible via the web at http://www.math.duke.edu/~username/ where username is your login name. If you omit the filename, as in this example, the file index.html will be displayed if present or an error given if it is not present.

To setup a personal webpage, here are the basic steps. Run these from a command prompt :

  • First create the directory ~/public_html if it does not already exist.
    • mkdir -p ~/public_html
  • Next set the proper permissions for the directory so that it can be entered by the web server.
    • chmod 701 ~/public_html  You should repeat this for any subdirectories of ~/public_html that you create.
  • Now create a file called index.html inside the directory ~/public_html using your favorite editor. kompozer is a nice WYSIWYG HTML editor.
    • kompozer ~/public_html/index.html Create your home page using the editor and save it to disk.
  • Finally set the permissions on index.html so that it is readable by the web server.
    • chmod 604 ~/public_html/index.html You should repeat this for any other files you place within ~/public_html.
  • Go to the URL http://www.math.duke.edu/~username/index.html replacing username with your login name and see if you get the webpage you just created.

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How do I print from Linux?

In general, the best way to print any type of file in Linux is from an application capable of viewing that file. So, print PDF files from a PDF viewer like acroread or evince. Print a DVI file from a DVI viewer like kdvi or xdvi and print Graphics files from an image viewer like kview or display. You can print some files from the command prompt, these include (to printer lw3 in this example):

  • Plain Text Files: Just run lpr -Plw3 filename.txt
  • Postscript Files: Use lpr -Plw3 filename.ps
  • DVI Files: Use dvips -Plw3 filename.dvi

Most other files should be printed from their applications.

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Where are the public printers? Can I print from my laptop via the wireless network?

Public Printers

There are 6 public printers in the department. A listing of these printers, their locations, and other facilites available within the department is available online.

Printing from the Wireless Network

The public printers are all accessible from the wireless network or from any Duke IP address. You should use IPP printing to connect to the server ipp://printhost.math.duke.edu with queue name /printers/lw0 for example. Full instructions for connecting to these printers and what drivers to use are available online.

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What classrooms have computers and how do I use them?

There are computers managed by the Mathematics Department in classrooms 047, 119, 205, 235, and 259 in the Physics Building. These rooms also provide cables for hooking up laptop computers for display via the over head projector. All computers in classrooms run the Linux operating system and should operate identically to the other Linux machines in the department.

There are also computers, managed by Arts & Sciences computing, in rooms 128 and 130. They run Windows or MacOS and require a NetID login.

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Do we have a scanner and how do I use it?

The department has a few of scanners available for your use.  The simplest method is to use the photo copier. It is capable of scanning many pages per minute and will send you an email with a PDF attachment of your scanned document. The only restriction is that scans will not be in color! Full instructions are available online as well as posted in the copy room.

The is also a scanner in room 102 that is part of the color printer. It is accessible over the network from any of the machines in the room. Further instructions are available online.

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How do I Move, Copy, or Delete a File from the Command Line?

Here are some useful commands to help you in managing your files:

  • ls: This command stands for List. If you type ls and press enter, a list of files in the current directory will be displayed. Useful options include ls -C which will show the list in a column format, and ls -l which will show the list is a long format with more information. You may also combine these with the option -a to show "All" files, including those that begin with a . and are thus called "hidden" since they do not display without the -a option, e.g. ls -al. Another useful option is ls -F which will differentiate file types in the listing by adding a @ to links, a / to directories, and a * to executable filenames.
  • cd: This command stands for Change Directory. If you have a subdirectory you wish to enter, you would type cd directory name. To go up a directory, you would type cd .. ( ..stands for one directory up, . stands for the current directory. )
  • cp: This command stands for Copy. It accepts two arguments , source and destination files. If the destination filename is a directory, the file is copied to that directory with the same filename as the source file. E.g. cp filename ~will copy the file filename to ~ (your Home Directory).
  • mv: This command stands for Move. It works similar to copy but the source file is removed after the copy.
  • rm: This command stands for Remove. It can accept any number of files. E.g. rm test.1 test.2 test.3 will remove the files test.1, test.2, and test.3.
  • mkdir: This command will Make a Directory. It can accept any number of directory names. E.g. mkdir test final group will create directories test, final, and group under the current directory.
  • rmdir: This command will Remove a Directory. In can accept any number of directory name BUT the directories to be removed must be empty.

NOTE SHORTCUT! If you are using the default command shell, csh, or tcsh, then any reference to your home directory can be abbreviated by the character ~. For example, cd ~/bin will change your "current directory" to the bin subdirectory of your home directory.

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How can I use PGP with Pine?

It is possible to configure the pine mail reader to use PGP (Pretty Good Privacy) Encryption when sending and receiving mail.

Configuring PGP

You need to first create your PGP key. Type pgp -kg, select the level of encryption, enter your name and your email address as shown in the example, enter a Pass Phrase (Important, you will need to enter this often, do not forget it), and then follow the directions on the screen. This should tell you it has generated a key. It will store this info in ~/.pgp. In general the defaults are sufficient.

Configure Pine to use PGP
  • Start Pine and go into the Setup -> Config menus.

  • The following is assuming the binary papp is located in /usr/local/bin. If not, please change the paths accordingly.

  • Near the end of the configuration options, change display-filters to this value : "-----BEGIN PGP" /usr/local/bin/papp -passfile _DATAFILE_ -key _PREPENDKEY_

  • Then change sending-filters to this value : /usr/local/bin/papp -encode -passfile _DATAFILE_ _RECIPIENTS_ -key _PREPENDKEY_

  • Now save the configuration and restart pine

Using PGP within Pine

Pine will automatically attempt to decode messages received that are encoded with PGP. It will prompt you for your passphrase and decode the messages automatically.
To encode a message, compose you message as usual, but after hitting CTRL-X to send the message, you can either use the default filter (no encoding) or use the PGP filter by pressing CTRL-N (next filter). If you use the PGP filter, the message will be send encoded with the recipients PGP public key if available. If not, it will warn you that you don't have their key. To add keys to your PGP keyring, run pgp -h for assistance.

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Where can I find documentation on Latex (TeTeX)?

Check out this page LaTeX/TeX (Courtesy Michael Kozdron and Laura Taalman).

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How can I use graphics with pdflatex?

See page 7 of the pdfTeX FAQ

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How do I create a PDF file from a Postscript or DVI file?

Converting a dvi file into a pdf file:

To convert the dvi file filename.dvi into the pdf file filename.pdf, type
dvipdfm filename

Converting a dvi file into a postscript file:

To convert the dvi file filename.dvi into the postscript file filename.ps, type
dvips filename

By Default, dvips now creates a ps file rather than directing the file to the printer.

Converting a postscript file into a pdf file:

To convert the postscript file filename.ps into the pdf file filename.pdf, type
ps2pdf filename.ps

Converting a EPS file into a pdf file:

To convert the postscript file filename.eps into the pdf file filename.pdf, type
pstopdf filename.eps

Converting a pdf file into a postscript file:

To convert the pdf file filename.pdf into the postscript file filename.ps, type
acroread -toPostScript filename.pdf or pdf2ps filename.pdf

You might want to try both to see which result looks better for your particular document.

Viewing and editing pdf files:

Acroread allows you to view your pdf files. To view filename.pdf, type
acroread filename.pdf

Very limited PDF editing may be done with the pdfedit application. To edit filename.pdf, type
pdfedit filename.pdf

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How can I post password protected web pages and files?

You can create subdirectories of your web tree in ~/public_html that are accessible only to those with a username and password you designate. Here are some instructions and warnings about this process.

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How do I allow certain users access to my files? What are ACLs?

ACLs are Access Control Lists. They allow you to set very fine grained permissions on files to grant permission for individual users, or groups of users, to read or write files that you own. Currently, you need to manage your ACLs from the command prompt and the configuration of ACLs is not trivial, it requires some knowledge of how permissions work on a unix system with regard to owners, groups, and others.

The best documentation I have found is available online at this page on Using ACLs with Fedora Core 2. Start there and let us know if you are having any problems. We can update our documentation here to help others if you have any suggestions.

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How can I mount my home directory from my home Linux machine?

The best way to mount your department home directory on your home linux machine is to use the Fuse kernel module and the Fuse program sshfs. This is installed on all machines manage that are running at least Fedora Core 4. If you need help installing it on another linux system, first check the sshfs homepage for info and then check with us if you need assistance.

To use sshfs, create a directory where you want to mount your home directory on your home machine, something like ~/math is approriate. Then run the command :

sshfs cauchy.math.duke.edu: ~/math

It will ask for your password (if your username is different on your home machine from the department, use username@cauchy.math.duke.edu: for the first argument where username is your user name on the department systems).

Now your math department directory is mounted on the directory ~/math on your local machine. When you want to unmount it you can either run the command :

fusermount -u ~/math

or in a pinch, kill the sshfs process that is running (killall sshfs will work).

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How can I mount my home directory from my home Windows or MacOSX machine?

WebDAV stands for "Web-based Distributed Authoring and Versioning." It is a set of extensions to the HTTP protocol which allows users to collaboratively edit and manage files on remote web servers. What that means is that you can store files in your home directory on the server and securely access them via standard https links for both upload and download. This allows you to store a ICS Calendar file for use with applications like Apple's iCal, Mozilla Sunbird, Evolution, KOrganizer, or any other WebDav enabled calendering application. Furthermore, it provides a method for mounting your home directory via the web on your home machine or laptop. For further infomation, see our page on WebDav Access.

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